题目内容：

Sixteen years ago a boy gave me an important gift. It was a smile.

It was the early autumn of my first year at a new school, and my old school was far away. 1. I was very lonely, and afraid to make friends with anyone.

Every time I heard the other students talking and laughing together, I felt sad. 2. Then one day, my classmates talked happily with their friends, but I sat at my desk unhappily as usual. At that moment, a boy came into the classroom. I didn’t know who he was. He passed me and then turned back. He looked at me with a smile. 3. It made me feel happy and warm. That smile changed my life. I started to talk with other students and made friends. Day by day, I became closer to everyone in my class. 4.

One day I asked him why he smiled, but he couldn’t remember smiling at me!

It doesn’t matter because all the dark days have gone. 5. If you think it lonely, you might always be alone. So smile at the world, and it will smile back.

根据短文内容，从方框中选出五个句子填入文中空缺处，使短文内容通顺完整。

A. Suddenly, I felt the touch of something bright and friendly.

B. Smile is very important in our life.

C. I couldn’t talk with anyone about my problems.

D. I believe that the world is what you think it is.

E. The boy with the lucky smile has become my best friend.

F. As a result, no one knew who I was.